Although the incidences of stroke are on the rise in Ireland, as many as 80 per cent of cases are thought to be preventable. By stopping smoking, becoming more active and drinking alcohol in moderation, a person’s likelihood of experiencing a stroke is significantly reduced.

The clot is fired “like a bullet from a gun” out of the heart.

Another contributory factor to stroke, albeit less well known, is atrial fibrillation (AF), a condition characterised by a fast or irregular heart beat.

“If you think of a cake mixer, the top part of the heart works on the same principle, agitating the blood before delivering it to the lower chambers of the heart that perform the pump action,” says Dr Ronan Collins, Director of Stroke Services at Tallaght Hospital in Dublin. “With atrial fibrillation, the heart doesn’t perform its mix action effectively, making it easier for a clot to form.”

When that happens, the results can be catastrophic. The clot, says Collins, is pushed down into the heart’s lower chambers and fired out into the system, “like a bullet from a gun.”

Most sufferers have no symptoms

While some people with AF will experience symptoms such as palpitations or breathlessness, the majority affected by the condition will have no symptoms at all.

“Unfortunately, the first time that many are aware a clot has formed is when it’s already caused a blockage,” says Collins.

When a blockage occurs inside an artery leading to the brain, it results in a stroke. Sometimes the clot will get jammed in an artery that serves another part of the body, such as the leg or the liver, where it also causes problems.

A stroke arising as a result of AF is likely to have particularly devastating consequences.

“They tend to be more severe and disabling strokes, and are also more likely to kill you,” says Collins. “Atrial fibrillation causes larger clots, which prove more difficult to dissolve.”

Although adults of any age can develop the condition, it is primarily seen in older age groups. Among the over-60s, an estimated five per cent will have AF; a figure that rises to 10 per cent in the over-75s.

Other risk factors associated with the condition include high blood pressure and diabetes.

Regular pulse checks

Collins advises a visit to the GP for patients in high-risk groups, where the doctor will perform a simple pulse test to check for irregularities.

Organisations such as Irish Heart also have instructional videos on their website (see below) that show people how to check their pulse.

“The videos tell you how to find the pulse and what it should feel like. If yours is abnormal, it’s important to see your doctor who can arrange an ECG,” says Collins.

Because AF can be intermittent and the condition is more likely to develop over time, pulse checks should be taken regularly.

Collins advises knowing what your blood pressure is and maintaining a healthy weight and active lifestyle, as well as limiting your alcohol intake, to reduce the chances of developing AF in the first place.

Managing the condition

To thin the blood in patients with AF, anticoagulants have traditionally been used.

While anticoagulants can be very effective in preventing clots, they requires regular monitoring, meaning frequent doctor’s visits and blood tests.

Fortunately, says Collins, the last few years have brought with them a number of new anticoagulants without some of the drug’s drawbacks.

The condition can sometimes be fixed with an electrically-controlled shock.

Once prescribed anticoagulants, it’s important that patients continue to take their medication as directed. Patients with AF are likely to revert to having an irregular heartbeat, even if a regular rhythm is restored for a time.

Younger patients, on the other hand, may benefit from a surgical procedure.

“The condition can sometimes be fixed with an electrically-controlled shock, or with ablation, where an instrument is inserted into the chamber of the heart to restore a regular rhythm,” explains Collins.

Whatever your age, it makes sense to get into good habits: stop smoking, be more active, keep your weight in check and learn how to take your pulse.